1. Field of the Invention
The present invention relates to a light-emitting module and an optical sight including the light-emitting module, in which significant adjustments may be made to the light-emitting module in different directions and without requiring disassembling of the optical sight.
2. Description of the Related Art
Referring to FIGS. 1, 2, and 3, a conventional optical sight includes a housing 10, an objective lens unit 11, an ocular lens unit 12, and a light-emitting module. The objective lens unit 11 is mounted to one end of the housing 10, whereas the ocular lens unit 12 is mounted to an opposite end of the housing 10. The housing 10, the objective lens unit 11, and the ocular lens unit 12 share a common central axis (C). The light-emitting module is mounted in the housing 10, and includes a casing 13, an emitter holder 14, two adjusting screws 15, a guide tube 16, a fixing screw 17, and a light emitter 18.
The casing 13 of the light-emitting module is formed with a pair of screw holes 131 that are separated by a predetermined distance along a first direction (X) which is perpendicular to the central axis (C), and is further formed with a first passage 132 positioned between the screw holes 131. The screw holes 131 and the first passage 132 extend through the casing 13 along a second direction (Z), which is parallel to the central axis (C). However, each of the screw holes 131 is separated from the central axis (C) by a predetermined distance.
The emitter holder 14 includes a frame section 141, a pair of flanges 143 extending from opposite sides of the frame section 141 along the first direction (X), and a second passage 142. The flanges 143 define elongated apertures 144, each of which opens outwardly from the frame section 141. The second passage 142 is substantially aligned with the first passage 132 of the casing 13.
The adjusting screws 15 are positioned respectively within the apertures 144 of the emitter holder 14, and engage respectively the screw holes 131 of the casing 13 to thereby secure the emitter holder 14 to the casing 13.
The guide tube 16 is mounted in the second passage 142 of the emitter holder 14.
The fixing screw 17 engages a radial screw hole (not visible) that is formed in the frame section 141 of the emitter holder 14, and that is in spatial communication with the second passage 142 of the emitter holder 14. By tightening the fixing screw 17, the position of the guide tube 16 within the second passage 142 of the emitter holder 14 may be secured.
The light emitter 18 is mounted in the guide tube 16, and is operable to project a light beam toward the objective lens unit 11. The beam of light projected from the light emitter 18 has an optical axis (L).
During manufacture of the optical sight, the guide tube 16 may be adjusted along the second direction (Z) to adjust a focal length of the light beam, that is, a distance of the light beam along the optical axis (L) from the light emitter 18, through the objective lens unit 11, and to a focal point. Further, by loosening the adjusting screws 15, the emitter holder 14 may be repositioned along the first direction (X), as well as along a third direction (Y), which is perpendicular to both the first and second directions (X,Z), thereby allowing for adjustment in the directionality of the optical axis (L). Following such adjustment, the light-emitting module is mounted in the housing 10, and the objective lens unit 11 and the ocular lens unit 12 are then mounted to opposite ends of the housing 10 as described above.
The conventional optical sight and light-emitting module have the following drawbacks:
1. Since the gaps between the adjusting screws 15 and the apertures 144 of the emitter holder 14 are relatively small, it is not possible to make any substantial adjustment of the light-emitting module along the third direction (Y).
2. True testing of the light beam projected by the light emitter 18 can be undertaken only after full assembly of the optical sight. As a result, if it is determined that further adjustment in the optical axis (L) and/or the focal length of the light beam projected from the light emitter 18 is required, the optical sight must be disassembled to allow for such adjustment. This is a time-consuming and labor-intensive process, particularly if multiple readjustments are necessary.